Talking about the testing principle and method of pressure sensitive tape initial tack tester
Pressure-sensitive tape is commonly known as self-adhesive tape. It has the characteristics of being easily bonded when using a small pressure, having a bonding effect in a short period of time, not polluting the adherend after peeling, and can be re-corrected when it is wrongly pasted, and it can be used for many times. The adhesive performance of the back glue surface is basically not affected and the reason for easy operation. The pressure-sensitive tape partially replaces the traditional method of mechanical fixation and the use of adhesives, such as transparent tape for sealing boxes, electrical tape for wire insulation, rubber glue, etc. used in daily life. With the development of polymer chemistry, the advancement of adhesive technology and processing equipment, tapes have been widely used in packaging, printing, automobiles, home appliances, electronics, medical, aviation, construction, telecommunication equipment and other industries, so they are widely used in many commodities and places. Adhesive products used in parts that are invisible to the naked eye are gradually increasing.
The initial tack is a property of the adhesive, which enables the adhesive to form a measurable bond under low pressure immediately after contacting the adhesive with the adherend. The quality of the initial viscosity of the adhesive is of great practical significance for some applications. For example, the quality of the initial viscosity of the neoprene adhesive for shoes in the shoemaking process has a great impact on the final adhesive quality of the shoes. great relationship. The initial tack performance of the pressure-sensitive adhesive tape is particularly important for the practicality of the pressure-sensitive adhesive tape. Below we will introduce in detail the initial tack test method of pressure-sensitive tape and the related instruments used.
my country's standard GB/T 4852-84 "Test method for initial viscosity of pressure-sensitive adhesive tapes (inclined rolling ball method)" clarifies the initial viscosity test method of adhesive tapes. The main point of this method is: in a slope of 30° On the inclined surface, the upper end is a 100mm-long roll-assist section with a polyester film bottom, and immediately following the roll-assist section is a 100mm-long test section with a pressure-sensitive adhesive tape to be tested. From the upper end of the rolling-assistance section, roll a steel ball with a certain diameter and mass downwards in a static state to see if it can be stuck in the test section after passing through the rolling-assistance section. Obviously large steel balls are not easy to stick. The diameter of the steel ball is 1/32 inch to 1 inch, and there are 33 kinds in total, which form a series.
Using the inclined rolling ball method to do the initial tack test is fast, easy to operate, requires little equipment investment, and does not require high operating proficiency. GB/T 4852-84 "Pressure-sensitive adhesive tape initial tack The test method (inclined rolling ball method)" has been implemented for more than ten years and has achieved good economic and social benefits. This test method should be mainly used for quality control, and the experimental requirements are relatively high: (1) The thickness of the adhesive layer of the pressure-sensitive adhesive tape to be tested remains constant; (2) There is no problem with the adhesive bonding with its backing material; ( 3) The stiffness of the backing material does not affect the sticking of the pressure-sensitive adhesive tape. Then the initial viscosity test of the inclined rolling ball method can have good repeatability, and can also detect the batch-to-batch variation in production.